The objectives of this research program are to: (1) Characterize the physiological effects of neurotoxins in sodium channels of neuroblastoma cells. (2) Compare the electrical excitability of normal and altered sodium channels of in different clonal lines. Specific neurotoxins of interest are veratridine, aconitine, batrachotoxin, graynotoxin, scorpion toxins and sea anemone toxins. This project will be studied utilizing suction pipet voltage clamp techniques in neuroblastoma cells. These studies will provide us insights into the function and structure relationship of sodium channels.